As a cocker x poodle is not a breed, and has no breed standard.. there really are no rules or worries on grooming. As long as you take it slow and safe, you can cut one into whatever style you wish. There is no correct way.

Also every dog looks different, with different coat length ability and type and can have or less of the attributes of one or the other of the breeds used.

My personal preference having cockers, is that I don't like the finished job and the dog looks just as mop like to me as it started. Personal taste, different strokes and all that.